1. Field of the Invention
The present invention relates to a safety system for a lawn mower having an engine, a propelling transmission system for transmitting drive from the engine to a propelling mechanism, and a PTO transmission system for transmitting the drive of the engine to a grass cutting unit.
2. Description of the Related Art
A riding type lawn mower or a relatively large lawn mower of the type handled by a walking operator has a self-propelling construction with drive of the engine transmitted to running devices as well as grass cutting blades. The self-propelled walking operator type lawn mower, for example, has various operating modes for selection, such as a self-propelled grass cutting operation in which both the propelling devices and cutting blades are driven, a grass cutting operation carried out with the operator pushing the lawn motor in which the propelling devices are stopped and only the cutting blades are driven, and a traveling mode in which the cutting blades are stopped and the propelling devices are driven.
When the engine of the lawn mower of this type is started with the grass cutting blades connected to the engine (i.e. with a cutting blade clutch engaged), for example, the cutting blade will suddenly begin rotating upon start of the engine. Further, while the lawn mower engages in a grass cutting operation or is just moved from one location to another in the self-propelled state with the engine running, the operator may inadvertently lose control of the lawn mower, such as by releasing his or her hold of the steering handle in the case of the walking operator type lawn mower or by leaving the driver's seat in the case of the riding type lawn mower. In such a situation, the lawn mower could run unattended away from the operator.